Rags and brushes have, to the present time, been almost exclusively used for the applications of thin coatings. By "thin coatings" is meant coatings having generally lower viscosities than the viscosities characteristic of interior and exterior paints and specifically coating materials which may be described, for purposes of ready reference, as stains and varnishes.
In coating stains for example, the most commonly used procedure is to saturate a rag, or a portion of a rag, with the stain, apply the stain containing portion of the rag to the surface to be stained and thereafter wiping the just-applied stained surface with a second rag for the purposes of removing the excess and smoothing the coated layer of stain uniformly and evenly over the surface being treated so as to avoid a final blotchy or uneven appearance. An alternative method is to apply a stain with a brush, and thereafter wipe the applied stain with a rag. The purpose of the rag is, again, to wipe off excess stain just applied by the brush, and to smooth the coated layer of stain uniformly and evenly over the surface being treated to avoid a blotchy or uneven appearance. The brush-rag process is less efficacious than the two-rag system in several respects, one being that a brush may not apply the coating to a thick enough depth, particularly when a non-planar surface is being treated such as a chair spindle, due to the separation of the filaments during the application strokes. If insufficient coating is initially applied by a brush, the insufficiency usually cannot be remedied by the subsequent wipe of a rag. And a third generally inefficient method of applying stain, which is usually used only on large flat surfaces, is to flood coat the surface area to be stained with the stain and thereafter wipe off the excess with a rag or rags. Although the possibility of insufficiency application of stain may not be great in flood-coating, this process is very wasteful of stained material and exceedingly messy.
The applicator of choice for varnish is a brush, though a combination of a brush and a rag and even, in rare occasion, flood-coating has been used. The disadvantage of using a brush to apply varnish is that brush strokes are frequently seen in the final finish, particularly when the varnish has been applied by the occasional user, such as a do-it-yourself consumer who is not skilled with a brush. Loose filaments are often shed from the brush and, if not noticed and removed while the varnish is still fresh, remain as an unsightly discontinuity in an otherwise smooth surface. Lint from a rag produces a similar undesirable result, and bubbles frequently appear in the final surface. In addition, considerable effort must be made to apply varnish uniformly a task which is more difficult than application of conventional paints for example, since varnishes are almost uniformly stickier and harder to work than paint. Both foam and brush filament brushes are prone to pump air into the applied coating, thereby creating undesirable bubbles in the final surface, though foam brushes are more apt to do so than filament brushes.
In summary, all of the above-described applicators and application methods are messy and wasteful. They are messy in that the user's hands invariably come in contact with the coating and this is true even when varnish is brushed on since invariably the user must pick up a loosened filament or a piece of lint, which has come loose from the applicator during use, and alighted on the coated surface where it is not desired. Said methods are wasteful in that the rag used to apply such coatings, at the end of a coating session, are loaded with coating which is of no further use and must be thrown away along with the rag. The greater the number of small jobs separated by a time span in which the coating-filled rags are fully or partially dried, the more wasteful is the rag or foam brush application process. Further, job requirements often dictate that the operator be confined to only one type of applicator and that specific need-dictated applicator may be undesirable for reasons peculiar to the user, such as an aversion to messy operations, or cost. Brushes for example, are not generally suitable for rounded curved surfaces, such as the spindles in a chair back or a round chair leg. Thus, the user is forced to use a flood-coating or, more likely, the rag application system with respect, particularly, to stains and varnishes.
Thus, there is an existing need for a type of applicator and method of application which is not messy, is not wasteful of coating material, which is applicable to both planar and non-planar surfaces, and which always results in a neat, smooth, uniform depth of coating.